Method of applying a photosensitive resin to a substrate for use in papermaking

Abstract

The invention comprises a method for applying a curable resin, such as a photosensitive resin, to a substrate such as a papermaker's dewatering felt. The method comprises the steps of providing a substrate; providing a curable liquid resin; providing a second material different from the curable liquid resin; applying the second material to the substrate to occupy at least some of the voids in the substrate intermediate the first and second surfaces of the substrate; applying the curable resin to the substrate; curing at least some of the resin to provide a resin layer on the substrate; and removing at least some of the second material from the substrate, wherein at least some of the second material is removed from the substrate after applying the curable resin to the substrate.

What is claimed: 
     
       1. A method of applying a photosensitive resin to a substrate to form an apparatus for use in papermaking, the method comprising the steps of: providing a substrate having a first surface, a second surface, and a thickness, the substrate having voids intermediate the first and second surfaces;   providing a liquid photosensitive resin;   providing a second material different from the liquid photosensitive resin;   providing a source of actinic radiation;   applying the second material to the substrate to occupy at least some of the voids in the substrate intermediate the first and second surfaces of the substrate;   removing at least some, but not all, of the second material from the substrate before applying the liquid photosensitive resin to the substrate;   applying the liquid photosensitive resin to the substrate to occupy at least some of the voids in the substrate;   exposing at least some of the liquid photosensitive resin to the actinic radiation; and   curing at least some of the photosensitive resin to provide a patterned resin layer disposed on the first surface of the substrate.   
     
     
       2. The method of claim 1 further comprising the step of substantially changing the viscosity of at least some of the second material applied to the substrate before the step of curing the resin. 
     
     
       3. The method of claim 1 further comprising the step of removing at least some of the second material from the substrate after applying the resin to the substrate. 
     
     
       4. The method of claim 1 further comprising the step of changing the phase of at least some of the second material applied to the substrate before the step of curing the resin. 
     
     
       5. The method of claim 1 further comprising the step of solidifying at least some of the second material applied to the substrate at a temperature between about 50 degrees Fahrenheit and about 150 degrees Fahrenheit prior to applying the resin to the substrate. 
     
     
       6. The method of claim 1 further comprising the step of cooling at least some of the second material applied to the substrate before the step of curing the resin, and the step of heating at least some of the second material applied to the substrate before a step of removing second material from the substrate. 
     
     
       7. The method of claim 1 wherein the second material comprises water. 
     
     
       8. The method of claim 1 wherein the second material comprises a component which is soluble in water. 
     
     
       9. The method of claim 1 wherein the second material comprises a solvent and a solute. 
     
     
       10. The method of claim 1 wherein the second material comprises a surfactant. 
     
     
       11. The method of claim 1 wherein the second material comprises an alcohol. 
     
     
       12. The method of claim 1 wherein the second material comprises a component selected from the group consisting of glycerol, polyoxyethylene glycol, polyoxypropylene glycol, and combinations thereof. 
     
     
       13. The method of claim 1 wherein the second material comprises a gelling agent. 
     
     
       14. The method of claim 13 wherein the second material comprises a soap gelling agent. 
     
     
       15. The method of claim 1 wherein the second material comprises a salt of fatty acids containing from about 12 to about 22 carbon atoms. 
     
     
       16. The method of claim 1 wherein the second material comprises a salt of fatty acids selected from the group consisting of sodium salts of fatty acids, potasium salts of a fatty acids, and combinations thereof. 
     
     
       17. The method of claim 1 wherein the second material comprises a gel forming agent selected from the group consisting of sodium laurate, sodium myristate, sodium palmitate, sodium stearate, potassium laurate, potassium myristate, potassium palmitate, potassium stearate, and mixtures thereof. 
     
     
       18. A method of applying a photosensitive resin to a substrate to form an apparatus for use in papermaking, the method comprising the steps of: providing a substrate having a first surface, a second surface, and a thickness, the substrate having voids intermediate the first and second surfaces;   providing a liquid photosensitive resin;   providing a second material different from the liquid photosensitive resin;   providing a source of actinic radiation;   providing a mask comprising regions opaque to the radiation and regions transparent to the radiation;   applying the second material to the substrate to occupy at least some of the voids in the substrate intermediate the first and second surfaces of the substrate;   providing a portion of the thickness of the substrate adjacent the first surface of the substrate which is substantially free of the second material;   applying the liquid photosensitive resin to the first surface of the substrate to occupy at least some of the voids in the portion of the thickness of the substrate which is substantially free of the second material;   positioning the mask intermediate the source of radiation and the coating of liquid photosensitive resin; and   exposing liquid photosensitive resin to the actinic radiation through the mask to induce curing of photosensitive resin in registration with the transparent regions in the mask to provide a patterned resin layer disposed on the first surface of the substrate.   
     
     
       19. The method of claim 18 wherein the substrate comprises a papermaker's dewatering felt. 
     
     
       20. A method of applying a photosensitive resin to a substrate to form an apparatus for use in papermaking, the method comprising the steps of: providing a substrate having a first surface, a second surface, and a thickness, the substrate having voids intermediate the first and second surfaces;   providing a liquid photosensitive resin;   providing a second material different from the liquid photosensitive resin;   providing a source of actinic radiation;   providing a mask comprising regions opaque to the radiation and regions transparent to the radiation;   applying the second material to the substrate to occupy at least some of the voids in the substrate intermediate the first and second surfaces of the substrate;   removing some, but not all, of the second material from the substrate prior to applying the liquid photosensitive resin to the substrate, to provide a portion of the thickness of the substrate adjacent the first surface of the substrate which is substantially free of the second material;   applying the liquid photosensitive resin to the first surface of the substrate;   positioning the mask intermediate the source of radiation and the coating of liquid photosensitive resin;   exposing the liquid photosensitive resin to the actinic radiation through the mask to induce curing of the photosensitive resin in registration with the transparent regions in the mask to provide a patterned resin layer on the first surface of the substrate;   removing at least some uncured photosensitive resin and second material from the substrate after curing photosensitive resin in registration with the transparent regions in the mask; and   post curing the photosensitive resin after removing substantially all of the second material from the substrate.   
     
     
       21. A method of applying a photosensitive resin to a papermakers dewatering felt, the method comprising the steps of: providing a papermakers dewatering felt having a first surface, a second surface, and a thickness, the papermakers dewatering felt having voids intermediate the first and second surfaces;   providing a liquid photosensitive resin;   providing a second material different from the liquid photosensitive resin;   providing a source of actinic radiation;   applying the second material to the papermakers dewatering felt to occupy at least some of the voids in the papermakers dewatering felt intermediate the first and second surfaces of the papermakers dewatering felt;   applying the liquid photosensitive resin to the papermakers dewatering felt;   exposing at least some of the liquid photosensitive resin to the actinic radiation; and   curing at least some of the photosensitive resin to provide a patterned resin layer disposed on the first surface of the papermakers dewatering felt.   
     
     
       22. The method of claim 21 further comprising the step of providing a portion of the thickness of the felt adjacent the first surface of the felt which is substantially free of the second material before applying the resin to the felt. 
     
     
       23. The method of claim 22 wherein the step of providing a portion of the thickness of the felt adjacent the first surface which is substantially free of the second material comprises removing some, but not all, of the second material from the felt before applying the resin to the felt. 
     
     
       24. The method of claim 21 further comprising the steps of: solidifying at least some of the second material applied to the felt before applying resin to the felt; and   removing some, but not all, of the second material from the felt before applying resin to the felt.   
     
     
       25. The method of claim 21 wherein the papermakers dewatering felt comprises a fibrous batt, wherein the step of applying the second material to the dewatering felt comprises applying the second material to the fibrous batt to occupy at least some voids in the fibrous batt, and wherein the step of applying the photosensitive resin to the dewatering felt comprises applying the resin to the fibrous batt.